Safety is a primary concern in the development of topical microbicides. Optical coherence tomography (OCT), a high-resolution, in-depth cross-sectional imaging modality, was utilized in conjunction with colposcopy to assess induced cervicovaginal epithelial changes that may predict product safety.
OCT and colposcopic images of macaque vaginal and cervical tissues were obtained in excised tissue and in vivo under various conditions, including mechanical injury and nonoxynol-9 treatment.
A scoring system was developed to categorize and quantify the OCT images based on morphologic features that indicate the presence or absence of an intact epithelial layer and inflammation. Using 3 categories (normal, mild to moderately abnormal, and severely abnormal), differences between healthy and injured tissue were apparent on OCT images. Normal images (category 1) had a bilayered structure representative of the epithelium and submucosa. Mild to moderately abnormal images (category 2) had areas of normal and abnormal epithelium. Severely abnormal images (category 3) had complete loss of the epithelium and/or inflammation, with loss of the bilayered structure on OCT.
OCT is a noninvasive imaging modality complementary to colposcopy. It distinguished between normal and abnormal (or injured) tissue and thus holds promise for safety evaluations of candidate microbicides and other vaginal products.
A noninvasive, high-resolution optical method was utilized to evaluate the state of cervicovaginal tissue. Normal and injured tissue were distinguishable, indicating a potential role for optical coherence tomography in microbicide safety evaluations.
From the *University of Texas Medical Branch, Texas; and †University of Washington, Washington
Supported by National Institutes of Health (U19 AI060598), National Institute of Child Health/Human Development of the National Institutes of Health (R01 HD40151), and Starpharma (Melbourne, Australia). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. We would also like to express our gratitude to Gracie Vargas, PhD, Dan Freeman, PhD, and Daniel Cowan, MD, for their support.
Correspondence: Kathleen L. Vincent, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0319. E-mail: firstname.lastname@example.org.
Received for publication May 26, 2007, and accepted September 9, 2007.